Astronauts must whenever they leave a spacecraft and are exposed to the environment of space. In space, there is no air to breath and no air pressure. Space is extremely cold and filled with dangerous radiation. Wearing a spacesuit allows an astronaut to survive and work in space.
Astronauts float around in space because there is no gravity in space. Everyone knows that the farther you get from Earth, the less the gravitational force is. Well, astronauts are so far from the Earth that gravity is so small. This is why NASA calls it microgravity.
Twelve astronauts walked on the Moon between 1969 and 1972. They were part of the six Apollo missions which each landed two astronauts on the Moon’s surface.
It takes about 3 days for a spacecraft to reach the Moon. During that time a spacecraft travels at least 239,000 miles, which is the distance between Earth and the Moon.